U.S. Pat. No. 4,669,469 to Gifford III et al.
a device for removing material from a blood vessel. A catheter is disclosed having a distally located cutter that separates deposits from the blood vessel. The catheter also defines a passageway which extends along its length to accommodate a flexible drive cable for rotating the cutter. An inflatable balloon at the distal end of the catheter is inflated to force the catheter wall against an atheroma attached to an inner lining of the vessel. This forces the atheromas into a cavity so it can be separated from the vessel wall by the cutter.
One perceived problem with the structure disclosed in the '469 patent is periodic clogging of the catheter with use. In the event the cavity becomes filled with material dislodged from the inner wall lining of the vessel, the entire catheter must be withdrawn from the subject. The cavity is then cleaned so that the catheter can be reinserted for further treatment of the vessel.